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A320405
Number of nX4 0..1 arrays with every element unequal to 0, 1, 2, 4 or 5 horizontally, vertically or antidiagonally adjacent elements, with upper left element zero.
1
8, 35, 156, 786, 3761, 18725, 92578, 463045, 2308299, 11536977, 57665448, 288255915, 1441171251, 7205071761, 36023566370, 180108084412, 900499990791, 4502306264686, 22510579308742, 112548275061883, 562718206201266
OFFSET
1,1
COMMENTS
Column 4 of A320409.
FORMULA
Empirical recurrence of order 83 (see link above)
EXAMPLE
Some solutions for n=5
..0..0..1..1. .0..0..1..0. .0..1..1..1. .0..1..1..1. .0..0..1..1
..0..1..1..1. .1..0..0..0. .0..1..1..1. .1..1..1..1. .0..1..1..0
..0..0..1..1. .0..0..1..0. .0..1..1..1. .1..1..0..1. .1..1..0..0
..1..1..1..0. .0..1..0..1. .0..1..0..0. .1..1..0..1. .0..1..1..1
..1..1..0..0. .0..0..1..1. .0..0..1..0. .1..1..1..0. .1..1..1..1
CROSSREFS
Cf. A320409.
Sequence in context: A114569 A189599 A302078 * A279379 A098999 A263520
KEYWORD
nonn
AUTHOR
R. H. Hardin, Oct 12 2018
STATUS
approved